tests: Bluetooth: Add BT Tester GAP smoke test

Add a babblesim test of the BT Tester doing a GAP smoke test
connecting 2 BT testers using BTP.

The purpose of this is to further increase the test coverage
of the BT Tester in CI, as it is only being built, and runtime
errors are typically not caught.

Signed-off-by: Emil Gydesen <emil.gydesen@nordicsemi.no>

tests/bluetooth/tester/CMakeLists.txt

@@ -7,6 +7,13 @@ LIST(APPEND QEMU_EXTRA_FLAGS -serial unix:/tmp/bt-stack-tester)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(tester)
 
+if(CONFIG_SOC_SERIES_BSIM_NRFXX)
+zephyr_include_directories(
+  ${BSIM_COMPONENTS_PATH}/libUtilv1/src/
+  ${BSIM_COMPONENTS_PATH}/libPhyComv1/src/
+  )
+endif() # CONFIG_SOC_SERIES_BSIM_NRFXX
+
 zephyr_library_include_directories(${ZEPHYR_BASE}/samples/bluetooth)
 zephyr_library_include_directories(${ZEPHYR_BASE}/subsys/bluetooth/mesh)
 zephyr_library_include_directories(${ZEPHYR_BASE}/subsys/bluetooth/host)

tests/bluetooth/tester/boards/nrf52_bsim.conf

@@ -0,0 +1,15 @@
+# CONFIG_TEST enforces minimal logging, which we don't want
+CONFIG_TEST=n
+
+CONFIG_ASSERT=y
+# Enable the option below to measure stack usage
+#CONFIG_INIT_STACKS=y
+CONFIG_THREAD_NAME=y
+
+CONFIG_LOG=y
+CONFIG_LOG_BACKEND_SHOW_COLOR=y
+
+CONFIG_LOG_DEFAULT_LEVEL=3
+CONFIG_BTTESTER_LOG_LEVEL_DBG=y
+
+CONFIG_UART_PIPE=n

tests/bluetooth/tester/boards/nrf5340bsim_nrf5340_cpuapp.conf

@@ -0,0 +1,24 @@
+# CONFIG_TEST enforces minimal logging, which we don't want
+CONFIG_TEST=n
+
+CONFIG_ASSERT=y
+# Enable the option below to measure stack usage
+#CONFIG_INIT_STACKS=y
+CONFIG_THREAD_NAME=y
+CONFIG_HW_STACK_PROTECTION=y
+
+CONFIG_LOG=y
+CONFIG_LOG_BUFFER_SIZE=4096
+CONFIG_RTT_CONSOLE=y
+CONFIG_LOG_BACKEND_RTT=y
+CONFIG_LOG_BACKEND_RTT_MODE_DROP=y
+CONFIG_LOG_BACKEND_RTT_MESSAGE_SIZE=256
+CONFIG_USE_SEGGER_RTT=y
+CONFIG_SEGGER_RTT_BUFFER_SIZE_UP=4096
+CONFIG_LOG_BACKEND_SHOW_COLOR=n
+CONFIG_LOG_PROCESS_THREAD_STACK_SIZE=1024
+
+CONFIG_LOG_DEFAULT_LEVEL=3
+CONFIG_BTTESTER_LOG_LEVEL_DBG=y
+
+CONFIG_UART_INTERRUPT_DRIVEN=y

tests/bluetooth/tester/src/btp.c

@@ -185,6 +185,19 @@ static void uart_send(const uint8_t *data, size_t len)
 {
 	uart_pipe_send(data, len);
 }
+#elif defined(CONFIG_SOC_SERIES_BSIM_NRFXX)
+extern void btp_register_tester(uint8_t *buffer, size_t len, uart_pipe_recv_cb cb);
+extern void btp_send_to_bsim(const uint8_t *data, size_t len);
+
+static void uart_init(uint8_t *data)
+{
+	btp_register_tester(data, BTP_MTU, recv_cb);
+}
+
+static void uart_send(const uint8_t *data, size_t len)
+{
+	btp_send_to_bsim(data, len);
+}
 #else /* !CONFIG_UART_PIPE */
 static uint8_t *recv_buf;
 static size_t recv_off;

tests/bluetooth/tester/src/main.c

@@ -2,14 +2,22 @@
 
 /*
  * Copyright (c) 2015-2016 Intel Corporation
+ * Copyright (c) 2025 Nordic Semiconductor ASA
  *
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <zephyr/autoconf.h>
+
 #include <zephyr/kernel.h>
+#include <zephyr/sys/util_macro.h>
 #include <zephyr/types.h>
 #include <zephyr/toolchain.h>
 
+#if defined(CONFIG_SOC_SERIES_BSIM_NRFXX)
+#include "bstests.h"
+#endif /* CONFIG_SOC_SERIES_BSIM_NRFXX */
+
 #include <zephyr/logging/log.h>
 #define LOG_MODULE_NAME bttester_main
 LOG_MODULE_REGISTER(LOG_MODULE_NAME, CONFIG_BTTESTER_LOG_LEVEL);
@@ -19,5 +27,10 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME, CONFIG_BTTESTER_LOG_LEVEL);
 int main(void)
 {
 	tester_init();
+
+#if defined(CONFIG_SOC_SERIES_BSIM_NRFXX)
+	bst_main();
+#endif /* CONFIG_SOC_SERIES_BSIM_NRFXX */
+
 	return 0;
 }

tests/bsim/bluetooth/tester/CMakeLists.txt

@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(tester_bsim)
+
+# Add the BSIM tester
+add_subdirectory(${ZEPHYR_BASE}/tests/bluetooth/tester ${CMAKE_BINARY_DIR}/tester_build)
+
+# This contains babblesim-specific helpers, e.g. device synchronization.
+add_subdirectory(${ZEPHYR_BASE}/tests/bsim/babblekit babblekit)
+target_link_libraries(app PRIVATE babblekit)
+
+# Add the testlib
+add_subdirectory(${ZEPHYR_BASE}/tests/bluetooth/common/testlib testlib)
+target_link_libraries(app PRIVATE testlib)
+
+zephyr_include_directories(
+  ${BSIM_COMPONENTS_PATH}/libUtilv1/src/
+  ${BSIM_COMPONENTS_PATH}/libPhyComv1/src/
+  )
+
+target_sources(app PRIVATE
+  src/btp.c
+  src/gap_central.c
+  src/gap_peripheral.c
+  src/test_main.c
+)

tests/bsim/bluetooth/tester/Kconfig

@@ -0,0 +1,4 @@
+# Copyright (c) 2024-2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+source "${ZEPHYR_BASE}/tests/bluetooth/tester/Kconfig"

tests/bsim/bluetooth/tester/Kconfig.sysbuild

@@ -0,0 +1,10 @@
+# Copyright (c) 2023-2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+source "${ZEPHYR_BASE}/tests/bluetooth/tester/Kconfig.sysbuild"
+
+config NATIVE_SIMULATOR_PRIMARY_MCU_INDEX
+	int
+	# Let's pass the test arguments to the application MCU test
+	# otherwise by default they would have gone to the net core.
+	default 0 if $(BOARD_TARGET_STRING) = "NRF5340BSIM_NRF5340_CPUAPP"

tests/bsim/bluetooth/tester/compile.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+# Copyright 2023-2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+#set -x #uncomment this line for debugging
+set -ue
+
+: "${ZEPHYR_BASE:?ZEPHYR_BASE must be set to point to the zephyr root directory}"
+
+source ${ZEPHYR_BASE}/tests/bsim/compile.source
+
+if [ "${BOARD_TS}" == "nrf5340bsim_nrf5340_cpuapp" ]; then
+  app=tests/bsim/bluetooth/tester \
+    tester=${ZEPHYR_BASE}/tests/bluetooth/tester \
+    conf_file=${tester}/prj.conf \
+    extra_conf_file="${tester}/boards/nrf5340bsim_nrf5340_cpuapp.conf" \
+    exe_name=bs_${BOARD_TS}_${app}_prj_conf sysbuild=1 compile
+else
+  app=tests/bsim/bluetooth/tester \
+    tester=${ZEPHYR_BASE}/tests/bluetooth/tester \
+    conf_file=${tester}/prj.conf \
+    extra_conf_file="${tester}/boards/nrf52_bsim.conf"  \
+    exe_name=bs_${BOARD_TS}_${app}_prj_conf sysbuild=1 compile
+fi
+
+wait_for_background_jobs

tests/bsim/bluetooth/tester/prj.conf

@@ -0,0 +1,2 @@
+# Please build using the sample configuration file:
+# ${ZEPHYR_BASE}/tests/bluetooth/tester/prj.conf

tests/bsim/bluetooth/tester/src/btp.c

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+
+#include <zephyr/drivers/uart_pipe.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/sys/util.h>
+#include <zephyr/sys_clock.h>
+
+#include "babblekit/testcase.h"
+
+#include "btp.h"
+
+LOG_MODULE_REGISTER(bsim_btp, CONFIG_BTTESTER_LOG_LEVEL);
+
+static uint8_t *btp_buffer;
+static size_t btp_buffer_len;
+static uart_pipe_recv_cb btp_cb;
+
+static uint8_t rsp_buffer[1024];
+static size_t rsp_buffer_len;
+static void wait_for_response(void)
+{
+	const uint64_t timeout_us = 10 * USEC_PER_SEC;
+	struct btp_hdr *rsp_hdr;
+
+	memset(rsp_buffer, 0, sizeof(rsp_buffer)); /* reset response buffer */
+	rsp_buffer_len = 0U;
+
+	WAIT_FOR(rsp_buffer_len > sizeof(*rsp_hdr), timeout_us, k_msleep(1));
+	rsp_hdr = (struct btp_hdr *)rsp_buffer;
+	if (rsp_hdr->len > 0) {
+		WAIT_FOR(rsp_buffer_len > sizeof(*rsp_hdr) + rsp_hdr->len, timeout_us, k_msleep(1));
+	}
+	rsp_buffer_len = 0U;
+}
+
+/* BTP communication is inspired from `uart_pipe_rx` to achieve a similar API */
+void btp_send_to_tester(const uint8_t *data, size_t len)
+{
+	size_t offset = 0U;
+
+	TEST_ASSERT(len > 0U);
+	TEST_ASSERT(data != NULL);
+	TEST_ASSERT(btp_buffer != NULL);
+	TEST_ASSERT(len <= btp_buffer_len);
+
+	memcpy(btp_buffer, data, len);
+
+	btp_buffer = btp_cb(btp_buffer, &offset);
+	TEST_ASSERT(offset == 0U);
+
+	wait_for_response();
+}
+
+void btp_register_tester(uint8_t *buffer, size_t len, uart_pipe_recv_cb cb)
+{
+	TEST_ASSERT(cb > 0U);
+	TEST_ASSERT(len > 0U);
+	TEST_ASSERT(buffer != NULL);
+
+	btp_buffer = buffer;
+	btp_buffer_len = len;
+	btp_cb = cb;
+
+	LOG_INF("%p %zu", buffer, len);
+}
+
+void btp_send_to_bsim(const uint8_t *data, size_t len)
+{
+
+	TEST_ASSERT(len > 0U);
+	TEST_ASSERT(data != NULL);
+	TEST_ASSERT(len <= ARRAY_SIZE(rsp_buffer));
+
+	/* TODO: Parse incoming data and call relevant handlers */
+	/* We will always get a `struct btp_hdr msg` first and then if len > 0 then some additional
+	 * data
+	 */
+	LOG_ERR("%zu", len);
+	memcpy(rsp_buffer + rsp_buffer_len, data, len);
+	rsp_buffer_len += len;
+}

tests/bsim/bluetooth/tester/src/gap_central.c

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <inttypes.h>
+#include <stdint.h>
+
+#include <zephyr/sys/util_macro.h>
+
+#include "babblekit/testcase.h"
+#include "bstests.h"
+
+#include "bttester.h"
+
+static void test_gap_central(void)
+{
+	TEST_PASS("PASSED\n");
+}
+
+static const struct bst_test_instance test_sample[] = {
+	{
+		.test_id = "gap_central",
+		.test_descr = "Smoketest for the GAP central BT Tester behavior",
+		.test_main_f = test_gap_central,
+	},
+	BSTEST_END_MARKER,
+};
+
+struct bst_test_list *test_gap_central_install(struct bst_test_list *tests)
+{
+	return bst_add_tests(tests, test_sample);
+}

tests/bsim/bluetooth/tester/src/gap_peripheral.c

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <inttypes.h>
+#include <stdint.h>
+
+#include <zephyr/sys/util_macro.h>
+
+#include "babblekit/testcase.h"
+#include "bstests.h"
+
+static void test_gap_peripheral(void)
+{
+	TEST_PASS("PASSED\n");
+}
+
+static const struct bst_test_instance test_sample[] = {
+	{
+		.test_id = "gap_peripheral",
+		.test_descr = "Smoketest for the GAP central BT Tester behavior",
+		.test_main_f = test_gap_peripheral,
+	},
+	BSTEST_END_MARKER,
+};
+
+struct bst_test_list *test_gap_peripheral_install(struct bst_test_list *tests)
+{
+	return bst_add_tests(tests, test_sample);
+}

tests/bsim/bluetooth/tester/src/test_main.c

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <stddef.h>
+
+#include "bstests.h"
+
+extern struct bst_test_list *test_gap_central_install(struct bst_test_list *tests);
+extern struct bst_test_list *test_gap_peripheral_install(struct bst_test_list *tests);
+
+bst_test_install_t test_installers[] = {
+	test_gap_central_install,
+	test_gap_peripheral_install,
+	NULL,
+};
+
+/* bst_main will be called by the BT tester's `main` function */

tests/bsim/bluetooth/tester/sysbuild.cmake

@@ -0,0 +1,6 @@
+# Copyright (c) 2023-2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+include(${ZEPHYR_BASE}/tests/bluetooth/tester/sysbuild.cmake)
+
+native_simulator_set_primary_mcu_index(${DEFAULT_IMAGE} ${NET_APP})

tests/bsim/bluetooth/tester/tests_scripts/gap.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+# Copyright 2023-2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+# Smoketest for GAP BTP commands with the BT tester
+
+simulation_id="tester_gap"
+verbosity_level=2
+EXECUTE_TIMEOUT=20
+
+source ${ZEPHYR_BASE}/tests/bsim/sh_common.source
+
+cd ${BSIM_OUT_PATH}/bin
+
+Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_tester_prj_conf \
+  -v=${verbosity_level} -s=${simulation_id} -d=0 -RealEncryption=1 -testid=gap_central
+
+Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_tester_prj_conf \
+  -v=${verbosity_level} -s=${simulation_id} -d=1 -RealEncryption=1 -testid=gap_peripheral
+
+Execute ./bs_2G4_phy_v1 -v=${verbosity_level} -s=${simulation_id} \
+  -D=2 -sim_length=20e6 $@ -argschannel -at=40
+
+wait_for_background_jobs #Wait for all programs in background and return != 0 if any fails